The publication of Copernicus's great work, "De Revolutionibus Orbium Celestium," was delayed until he was advanced in years, because his astronomical opinions were constantly progressing; and, with the patience of true genius, he was not satisfied with anything less than the perfect expression of truth as he saw it. It has sometimes been said that it was delayed because Copernicus feared the storm of religious persecution which he foresaw it would surely arouse. How utterly without foundation is this pretence, which has unfortunately crept into serious history, can be seen from the fact that Pope Paul III accepted the dedication of the work; and of the twelve popes who immediately followed Paul not one even thought of proceeding against Copernicus's work. His teaching was never questioned by any of the Roman Congregations for nearly one hundred years after his death. Galileo's injudicious insistence in his presentation of Copernicus's doctrine, on the novelties of opinion that controverted long-established beliefs, was then responsible for the condemnation by the Congregation of the Index; and, as we shall see, this was not absolute, but only required that certain passages should be corrected. The corrections demanded were unimportant as regards the actual science, and {34} merely insisted that Copernicus's teaching was hypothesis and not yet actual demonstration. It must not be forgotten, after all, that the reasons advanced by Copernicus for his idea of the movements of the planets were not supported by any absolute demonstration, but only by reasons from analogy. Nearly a hundred years later than his time, even after the first discoveries had been made by the newly constructed telescopes, in Galileo's day, there was no absolute proof of the true system of the heavens. The famous Jesuit astronomer, Father Secchi, says the reasons adduced by Galileo were no real proofs: they were only certain analogies, and by no means excluded the possibility of the contrary propositions with regard to the movements of the heavens being true. "None of the real proofs for the earth's rotation upon its axis were known at the time of Galileo, nor were there direct conclusive arguments for the earth's moving around the sun." Even Galileo himself confessed that he had not any strict demonstration of his views, such as Cardinal Bellarmine requested. He wrote to the Cardinal, "The system seems to be true;" and he gave as a reason that it corresponded to the phenomena.